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cation of MOF materials as catalysts for carbon dioxide transformation into
methanol are listed in comparison with the conventional catalysts. Three different
routes for carbon dioxide conversion are included individually: catalytic hydrogenation, photocatalysis, and electrocatalysis.
Keywords Carbon dioxide · Greenhouse gases · CO 2 hydrogenation · Methanol
synthesis · Metal organic framework · MOF · Catalytic hydrogenation ·
Photocatalysis · Electrocatalysis · CO 2 reduction
Abbreviations
GHGs Greenhouse gases
MOFs Metal organic frameworks
TOF
Turnover frequency
3.1 Introduction
Global warming is a catastrophic development that may destroy the future and the
survival of human on the earth. The essential reason for the observed climate change
since the mid-twentieth century is the emission of greenhouse gases (GHGs).
Greenhouse gases include carbon dioxide (CO 2 ), methane (CH 4 ), nitrous oxide
(N 2 O), hydrofluorocarbon (HFC), perfluorocarbons (PFCs), and sulfur hexafluoride
(SF 6 ) (Ouda et al. 2016). Carbon dioxide emissions are presenting about 83% of the
detected greenhouse gases (Lai 2008).
The emission of greenhouse gases is considered to have caused approximately 1
degree Celsius of global warming higher than the average of the preindustrial period
(before 1900). Global warming is likely to reach 1.5 °C between 2030 and 2052, if
it continues to increase at the current rate (Masson-Delmotte et al. 2018).
The emissions of carbon dioxide (CO 2 ) are playing the critical role in the warming of the atmosphere (Khan et  al. 2013; Al-Maamary et  al. 2017). In 2014, the
concentration of carbon dioxide has reached 400  ppm and is accompanied with
0.8  °C increase in global surface temperature (Pachauri and Allen 2014).
Successively, the concentration of the atmospheric carbon dioxide has increased to
409 ppm, which is associated with sequential increase in global surface temperature
(Kumar et  al. 2018). Regarding the current rates of carbon dioxide emissions all
over the world, the expected concentration of atmospheric carbon dioxide at this
century will be ranged between 600 and 700  ppm. This dramatic increase in the
concentration of carbon dioxide, in the environment, may lead to the warming up of
the earth’s surface by 5 °C (Leung et al. 2014).
On 12th December 2015, around 190 countries met in Paris, France, under the
umbrella of the 2015 United Nations Climate Change Conference, COP 21. The
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